We need a reason to believe the fourth installment can resurrect the franchise.

The trilogy gave us one of the best basketball stories ever told, so it hasn’t been all bad. The debut of Warriors-Cavaliers in 2015 was exciting, because it was new, and even though Kyrie Irving and Kevin Love didn’t make the final cut, LeBron was enough to make it entertaining opposite a Golden State team that didn’t know how good it was yet. We didn’t know, either, until the following year, when the Warriors were a 73-win monster. Then, LeBron and company tamed the beast, and boy was that epic. Then, Kevin Durant signed on in 2017, Golden State jumped the shark and audiences went home early.

We didn’t need a fourth installment, not with George Hill reprising the role of a beloved character. This is not 2016. Those Warriors did not have Durant, and these Cavaliers do not have Irving. This is more like when they made “Home Alone 4” with somebody you’ve never seen since playing Macaulay Culkin’s part, and the storyline picked up eight months after Kevin McCallister’s parents separated.

We’ve seen stars resuscitate failing tetralogies before, and this series has no shortage of headliners. We won’t know for sure if this one’s a complete dud until we at least see the opening act, so here are three reasons to believe that the Cavs can be to the Warriors what Balboa was to Drago in “Rocky IV.”

Only the strong survive, and Cleveland Cavaliers superstar LeBron James might be the strongest. (Getty Images)

LeBron James alone is reason to watch

LeBron is Jack Nicholson in his prime. You buy your ticket before you even know who else is playing.

This is LeBron’s eighth straight trip to the Finals, and every year he gives us a show. If you’re a fan of greatness, you’re at least watching until you know the outcome, because he just submitted one of the great six-game stretches of basketball you’ll ever see, averaging 37 points on 55 percent shooting (46 percent from 3-point range), nine rebounds and eight assists to slay the Boston Celtics. To not see what he does for an encore means not enjoying transformative experiences, and that’s no way to be.

Even if you’re someone who dislikes LeBron, detests his entitlement about every call, all as he uses his God-given strength to trample opponents on the other end, and despises his “Decision” to join two other Hall of Famers in a quest for rings, because Michael Jordan wouldn’t stand for that, you’re probably going to watch until the end, because you want to make sure the killer isn’t getting up again.

And there’s another thing: This might be your last chance to see LeBron on this stage. If he stays in Cleveland, a Boston team that adds Irving and Gordon Hayward might even be too big a mountain for him to climb, and he might not even be favored against a more seasoned Philadelphia 76ers squad.

This summer, LeBron may join those Sixers, form a new super team in Los Angeles or force his way to Houston, but if he reaches a ninth straight Finals under another scenario, he won’t be the underdog he is now, and there’s still something to seeing Goliath play the role of David after all these years.

Andre Iguodala and the absence of a supporting cast

Warriors forward Andre Iguodala won the 2015 Finals MVP award for his work opposite LeBron, who willed the Cavaliers to six games and averaged 36 points (albeit on 40 percent shooting), 13 rebounds and nine assists for the series, despite working without his two best teammates for all but 44 minutes.

This is your reminder that LeBron is quite good and even an MVP-worthy defensive effort against him is barely enough to keep him from bullying you by himself. At age 34, Iguodala is probably still Golden State’s best option against LeBron. His absence from the Western Conference finals due to a left leg contusion was so palpable that Warriors coach Steve Kerr conceded it cost his team at least two wins in the series (and maybe more, had Chris Paul not strained a hamstring for Games 6 and 7).

The Warriors can also throw Durant and Klay Thompson at the four-time MVP, but the fewer bodies available to defend LeBron, the fewer fouls there are to parse out when he backs you down 27 feet from the basket. Chasing a 250-pound boulder of a man can also be pretty taxing on guys who need some energy on offense. Ask Marcus Morris, Jayson Tatum and Jaylen Brown how much fun that is.

Iguodala missed the final four games against Houston, and his status for Game 1 of the Finals remains uncertain. It seems as though he will return at some point in the series, but his health will determine how much the Warriors can roll out the death lineup of Iguodala, Durant, Thompson, Draymond Green and Stephen Curry. That All-Star quintet can run Tristan Thompson off the floor, negating the Cavs center’s effectiveness as a paint-protecting defensive stalwart and an offensive rebounding machine.

Cleveland had roughly seven effective players against Boston, and removing Thompson from that mix is asking even more from guys like J.R. Smith, Kyle Korver and Jeff Green, especially with Love still working his way out of concussion protocol. They’re already at a breaking point. Going small probably means more Jordan Clarkson, and that’s when the rock they’re pushing uphill rolls back over them.

Even if Iguodala returns, these Warriors are shallow, too. They’re not the 2015 edition, running a five-man bench unit featuring a pair of ex-All-Stars and a former Sixth Man of the Year, and they’re not even last year’s version, comfortable enough to play Zaza Pachulia, David West and Patrick McCaw a combined 39 minutes per game in the playoffs. Pachulia lost his job to the more athletic Kevon Looney and JaVale McGee, neither of whom should even scare Larry Nance Jr. West is on the 19th hole of his storied career, and McCaw just returned from a frightening fall that cost him nearly two months.

Beyond Shaun Livingston, Golden State can’t feel great about anyone else outside the Hamptons Five. Jordan Bell, Nick Young and Quinn Cook won’t put the fear of God into a Cavs team that’s seen better bit players. Even the death lineup has shown signs of mortality in recent weeks, with Thompson and Curry both overcoming knee strains to different degrees. And, hey, Green could go off script and punch somebody in the groin again; this whole burner account saga could throw Durant off his game.

At some point, LeBron will steal the show if the Warriors’ star-studded ensemble requires enough stand-ins, and we won’t know that point until the final curtain closes and they all take their bow.

Golden State Warriors star Stephen Curry can take the torch and light a series on fire. (Getty Images)

Stephen Curry hasn’t been the main Finals attraction yet

There is nothing more entertaining in the NBA than when Curry gets cooking, particularly when he plugs into the Oracle Arena crowd. It’s electric, and we haven’t seen that on a Finals stage in a while.

It’s strange to say about someone who has made six or more 3-pointers in five of his 18 career Finals games, including three separate 7-of-13 performances from beyond the arc, but with a title on the line he’s either been overshadowed by LeBron, Durant or a strained knee in his three previous showings.

Curry is a two-time MVP, building his own legacy as an all-time great, and he’s yet to have a signature Finals moment like LeBron’s Game 7 chase-down block of Iguodala in 2016 or Durant’s Game 3 pull-up triple over LeBron last year. We have years worth of highlight reels from Curry, but there’s something about those Finals clips — Michael Jordan sealing Game 6 in 1998 and Magic Johnson’s sky hook to win Game 4 in 1987 among them — that singe an all-timer’s greatness into our memories forever.

Unfair for the most part, we’ve heard our share of criticisms against Curry since his unanimous MVP season — how his flashiness gets lost in the Finals spotlight, his defense doesn’t compare to a Chris Paul, his force of will can’t match a Russell Westbrook and his brand of basketball requires a Durant to alleviate the pressure. He needs an unforgettable moment for his portfolio, and he needs to win Finals MVP over LeBron and Durant if he wants to climb the pantheon. I can’t wait to see if he does it.

We could break down X’s and O’s all day to figure out how this series could be competitive. We could talk about how the Cavs succeeded against the Celtics by alternating between a formidable offense that fires 30-plus 3’s at a 40 percent clip at home to a switchable defense that holds an opponent to 79 points on the road. We could examine why the Warriors went away from the freewheeling motion offense that’s made them so successful to an iso-heavy style relying on Durant to beat the Rockets.

But that’s not why we tune in for Warriors-Cavaliers IV. We want to see LeBron’s one-man production. We want to see which supporting cast members rise to the occasion. We want to see Curry steal the show. We want to see something we’ve never seen before or never will again, and there’s reason to believe this cast of characters can cover both genres. If not, well, let’s hope this is the last installment.